Around 0 BBY, Gyaos Vader captured the Jedi MasterObi-Wan Kenobi and held him prisoner on Kessel,[1] the asteroid-shaped planet.[4] The young TatooinianLuke Skywalker, who had began his Jedi training under Kenobi, came to the rescue of his Master. Once Skywalker reached the creature's lair in the temple, he faced Gyaos Vader, who had taken the shape of the Lord Vader in order to surprise him. Both opponents drew their lightsabers and engaged in a duel. During the fight, the creature turned back to its true shape and began flying around the room. Skywalker and the changeling traded several blows, but the young Jedi got the upper hand. Having killed Gayos Vader, Luke Skywalker freed Master Kenobi and set off for Iskalon, where the goldendroidC-3PO had been been taken hostage by another shapeshifter.[1]

According to both "Game On!", an article published in the Star Wars Insider 135, as well as the game manual, the fake Vaders (Clados, Gyaos, Sasori and Wampa) were said to have been "intended as illusions representing Luke's fears, like the Cave of Evil scene in Empire Strikes Back."[6] However, since those game opponents were able to kidnap Luke Skywalker's allies and hold them prisoner,[1] this article assumes they were real creatures rather than mere illusions. Additionally, the Vader-shaped figure that Skywalker fought in the Cave of Evil was more than mere illusion, being in fact a protean dark side entity known as the Dark Spirit.[7]